Electrical connector



Dec. 16, 1947. J. M. VAN VLEET 2,432,636

ELECTRICAL CONNECTOR Filed NOV. 29, 1943 INVENTOR. z//m/ 44 M/v Mffr BYEL Arm/PMX Patented Dec. 16, 1947 ELECTRICAL CONNECTOR John M. VanVleet, Wauwatosa, Wis., assigner to Kyle Corporation, South Milwaukee,Wis., a corporation of Wisconsin Application November 29, 1943, SerialNo. 512,136

This invention relates to electrical connectors and is particularlydirected to the type of electrical connector in which a bifurcated boltis employed and adapted to receive the electrical conductors between thespaced arms oi the bolt, and in which a sliding plunger i's urged toclamp the conductors by means of a nut screwed on the bolt and coactingwith the sliding plunger.

In the connectors as heretofore constructed of this general type it hasbeen the practice to use V-threads. It has been found that with theheretofore known types of connectors the reaction between thethreads ofthe bolt and the threads of the nut when the nut is tightened producesresultant forces which tend to move the spaced arms of the bolt towardseach other into binding engagement with the sliding plunger so that aconsiderable portion of the force exerted by the nut was needed toovercome the enormous friction between the arms and the plunger, thisfriction increasing as the bolt is tightened. Additionally it was foundin connectors as heretofore constructed that the effective area ofcontact between the threads of the nut and bolt decreased as the nut wastightened due to the inward motion of the spaced arms of the bolt andfrequently the area of contact became so small that the threadsstripped.

This invention is designed to overcome the above noteddefects, andobjects of this invention are to provide an electrical connectoremploying a bifurcated bolt with spaced arms and a sliding plungertherebetween and a nut threaded on the bolt and coacting with theplunger, in which the coacting faces of the threads of the nut and thebolt which transmit the force from the nut to the bolt are so arrangedthat no resultant forces are produced tending to force the spaced armsof the bolt into binding engagement with the sliding plunger, to therebyavoid binding between the sliding plunger and the spaced arms of thebolt and to maintain the eiective area of contact between the threads ofthe bolt and the threads of the nut the same as it was before the nutwas tightened.

Embodiments of the invention are shown m the accompanying drawings, inwhich:

Figure 1 is a view of the connector in clamping position.

Figure 2 is a side view of the connector with the conductors in section.

Figure 3 is a sectional view on the line 3--3 of Figure 2.

Figure 4 is a sectional view drawn to an enlarged scale on the line 4-4of Figure 3.

3 Claims. (Cl. 24-135) shank 5 of the sliding plunger.

Figure 5 is a view showing the nut and sliding plunger removed from thebifurcated bolt, the nut being shown in section corresponding to asection on the line 5--5 of Figure 3.

Figure 6 is a view corresponding to Figure 4 showing a modified form ofthe invention.

Referring to Figures 1 through 5, it will be seen that the connectorcomprises a bifurcated boit I having a pair of arms 2 extending from thehexagonal or other type of polygonal head 3. The arms 2 are spaced apartto provide a channel whose upper end is rounded as indicated at 4.

A sliding plunger 5 having a shank 5 normally positioned between thearms 2 is provided. The plunger includes a head 6 which has a channel 1in its upper face. The head is provided with outwardly projectingshouldered portions 8, see Figure 5. A nut 9 bears against theshouldered portion 8 and is loosely retained againstl separation fromthe sliding plunger by means of a pair of ears l0 struck or shearedoutwardly from the The nut 9 is threaded on the bolt and is adapted tomove the plunger inwardly or outwardly.

It is to be noted particularly that the bolt and nut are provided withsquare threads so that there are fiat faces of contact between thethreads of the nutand the threads of the bolt, thereby avoiding anytendency to force the arms 2 towards each other when the nut istightened.

In using the device the connector is slipped over a conductor such asindicated at Il and a second conductor I2 is positioned between the arms2. Thereafter the plunger 5 is inserted between the arms and the nutscrewed onto the bolt so as to clamp the two conductors tightly togetherand in contact respectively with the head 3 of the bolt and the head 6of the plunger. A very iirm and excellent electrical connection is thusobtained.

Of primary importance in this invention is the fact that the surface ofengagement between the threads of the bolt and the threads of the nut isa at surface and thus there is no cam action tending to force the arms 2towards each other, as has heretofore been the case where the usualV-type threads were employed. In connectors having V-type threads greatdifliculty has been encountered due tothe fact that the cam actionbetween the threads of the nut and the threads of the bolt had aresultant which forced the arms towards each other, therebycausing'tight binding between the sliding plunger and the arms of thebifurcated bolt. A great deal of force was expended in merely forcingthe plunger inwardly after clamping engagement had started, and as Withthis invention there is no tendency to force the arms 2 of thebifurcated bolt towards each other into clamping engagement with theshank oi the sliding plunger. Instead the sliding plunger is freelyslidable between the arms under all conditions and no matter how tightlythe conductors are clamped together there is no side thrust imparted tothe arms 2 which would tend to clamp the sliding plunger against freesliding motion.

The invention may take other forms provided the active engaging facesbetween the threads of the nut and the threads of the bolt are at facesso that the transmission of force from the threads of the nut to thethreads of the bolt is across the iiat faces when the connector istightened. For example, buttress threads may be employed as shown inFigure 6. In this form of the invention the nut is indicated by thereference character 9 and a portion of one of the arms of the bifurcatedbolt is indicated by the reference character 2. The engaging faces 9"and 2" between the threads of the nut and the threads of the bolt whichtransmit the pressure from the bolt to the nut are fiat faces. By usingbuttress threads a slightly stronger mechanical constructionis obtainedthan where square threads are employed as in the rst form of theinvention. The principle, however, is identically the same in bothforms.

It is preferable to make the bolt, the plunger and the nut of materialhaving good electrical conducting qualities,

It will be seen that a very simple and serviceable type of connector hasbeen employed which has all of the advantages of connectors of this typeand in addition has the very decided advantage of preventing bindingbetween the arms of the bifurcated bolt and the sliding plunger.Inasmuch as there is no decrease in the eiective area of contact betweenthe threads of the bolt and the threads of the nut as the nut istightened, there is no tendency to strip the threads due to a decreasein effective area of contact as in the prior types of connectorspreviously discussed.

It will be seen further that the connector is of very simpleconstruction and is easy to produce.

Although this invention has been described in considerable detail, it ist be understood that such description is intended as illustrative ratherthan limiting, as the invention may be variously embodied and is to beinterpreted as claimed.

I claim:

1. A connector for connecting electric conductors comprising abifurcated threaded bolt having a pair of spaced arms adapted to receiveconductors therebetween and a head portion Joining said spaced arms atone end, a slidingl plunger slidable between said spaced arms, and athreaded nut coacting with said bolt and operatively engaging saidsliding plunger to force said sliding plunger into clamping relation tothe electricalA conductors placed between the spaced arms, the threadsof said bolt and the threads of said nut having flat coacting faces theelements of which lie on radial lines at right angles to the axis ofsaid bolt, whereby when said nut is tightened there are no resultantforces tending to move the spaced arms towards each other into bindingengagement against said sliding plunger.

2. A connector for connecting electric conductors comprising abifurcated threaded bolt having a pair of spaced arms adapted to receiveccnductors therebetween and a, head portion joining said spaced arms atone end, a sliding plunger slidable between said spaced arms, and athreaded nut coacting with said bolt and operatively engaging saidsliding plunger to force said sliding plunger into clamping relation tothe electrical conductors placed betwe'en the spaced arms, the threadsof said nut and the threads of said bolt being square threads, wherebywhen said nut is tightened there are no resultant forces tending to movethe spaced arms towards each other into binding engagement against saidsliding plunger.

3. A connector for connecting electric conduc-` tors comprising abifurcated threaded bolt having a pair of spaced arms adapted to receiveconductors therebetween and a, head portion joining said spaced arms atone end, a. sliding plunger slidable between said spaced arms, and athread,- ed nut coacting with said bolt and operatively engaging saidsliding plunger to force said sliding plunger into clamping relation tothe electrical conductors placed between the spaced arms, the threads ofsaid nut and the threads of said bolt being buttress threads havingtheir interengaging iiat faces eilective in transmitting the force fromthe nut to the bolt when the nut is tightened, whereby when said nut istightened there are no resultant forces tending to move the spaced armstowards each other intobinding engagement against said sliding plunger,

JOHN M. VAN VLEET.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTSy Number Name Date 597,748 Shults Jan. 25, 18981,881,593 Hossfeld Oct. 1l, 1932 1,943,677 Kearney Jan. 16, 19342,088,481 Mylius July 27, 1937

